- One-step preparation of flower-like poly(styrene-co-zwitterionic ionic liquid) microspheres with hierarchical structures for supported acidic heterogeneous catalysts
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By using a one-step copolymerization of styrene (St) and 3-(1-vinyllimidazolium-3-yl)propane-1-sulfonate (VIPS), a kind of poly(St-co-VIPS) microsphere, with a hierarchical structure composed of nanospheres or nanoparticles with diameters in the range of 70-90 nm arranged on its surface and that look like a flower, has been simply prepared in the presence of polyvinyl pyrrolidone (PVP) in an aqueous alcohol system. A formation mechanism of the flower-like poly(St-co-VIPS) microspheres is proposed by investigating the influence of reaction conditions on its morphologies and observing its growth process with time. Because of the existence of zwitterionic liquid functional groups, flower-like poly(St-co-VIPS)-acid microspheres, a novel kind of heterogeneous catalyst, were successfully prepared by immobilizing heteropoly acids and H2SO4 on the flower-like poly(St-co-VIPS) microspheres, and the heterogeneous catalysts showed better catalytic activities for esterifications, acetalizations and transesterifications than with H2SO4 as the catalyst. Especially, the heterogeneous catalysts presented excellent catalytic efficiency for the acetalization of benzaldehyde and 1,2-propanediol, which could successfully reach 96.2%. Furthermore, the crosslinked flower-like poly(DVB-co-VIPS)-H2SO4 microspheres prepared under the same conditions where only St was replaced by divinyl benzene (DVB) have better reusability than that of the flower-like poly(St-co-VIPS)-H2SO4 with poor solvent resistance, and could be reused four times without significant loss of the catalytic activity, indicating that they could act as excellent recyclable heterogeneous catalysts for the synthesis of acetals and have potential application in industry.
- Mao, Hui,Song, Yang,Qian, Dongmei,Liu, Daliang,Wu, Shuyao,Zhang, Yu,Hisaeda, Yoshio,Song, Xi-Ming
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Read Online
- Visible-Light Mediated Oxidative Fragmentation of Ethers and Acetals by Means of Fe(III) Catalysis
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A new method employing iron(III) acetylacetonate along with visible light is described to effect oxidative ring opening of cyclic ethers and acetals with unparalleled efficiency. The method allows for a photocatalytic radical chemistry approach to functionalize relatively inert cyclic ethers into useful synthetic intermediates. The methodology sheds further light on the use of underexplored iron complexes in visible-light photochemical contexts and illustrates that simple Fe(III) complexes can initiate redox processes from 4LMCT excited states.
- Lindroth, Rickard,Ondrejková, Alica,Wallentin, Carl-Johan
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supporting information
p. 1662 - 1667
(2022/03/14)
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- Soluble/MOF-Supported Palladium Single Atoms Catalyze the Ligand-, Additive-, and Solvent-Free Aerobic Oxidation of Benzyl Alcohols to Benzoic Acids
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Metal single-atom catalysts (SACs) promise great rewards in terms of metal atom efficiency. However, the requirement of particular conditions and supports for their synthesis, together with the need of solvents and additives for catalytic implementation, often precludes their use under industrially viable conditions. Here, we show that palladium single atoms are spontaneously formed after dissolving tiny amounts of palladium salts in neat benzyl alcohols, to catalyze their direct aerobic oxidation to benzoic acids without ligands, additives, or solvents. With this result in hand, the gram-scale preparation and stabilization of Pd SACs within the functional channels of a novel methyl-cysteine-based metal-organic framework (MOF) was accomplished, to give a robust and crystalline solid catalyst fully characterized with the help of single-crystal X-ray diffraction (SCXRD). These results illustrate the advantages of metal speciation in ligand-free homogeneous organic reactions and the translation into solid catalysts for potential industrial implementation.
- Tiburcio, Estefanía,Greco, Rossella,Mon, Marta,Ballesteros-Soberanas, Jordi,Ferrando-Soria, Jesús,López-Haro, Miguel,Hernández-Garrido, Juan Carlos,Oliver-Meseguer, Judit,Marini, Carlo,Boronat, Mercedes,Armentano, Donatella,Leyva-Pérez, Antonio,Pardo, Emilio
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supporting information
p. 2581 - 2592
(2021/02/16)
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- MOFs based on 1D structural sub-domains with Br?nsted acid and redox active sites as effective bi-functional catalysts
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A novel family of lamellar MOF-type materials, which contain Br?nsted acid sites together with redox active centers, based on assembled 1D organic-inorganic nanoribbons were obtained through direct solvothermal synthesis routes, using specific monotopic benzylcarboxylate spacers with thiol substituents in thepara-position like structural modulator compounds and effective post-synthesis oxidized treatments to generate accessible sulfonic groups. Low-dimensional aluminum metal-organic materials, containing free sulfonic pendant groups (Al-ITQ-SO3H), were successfully tested in several acid reactions, such as acetalization, esterification and ring opening of epoxides with a significant impact on fine chemistry processes. The direct introduction of stabilized Pd nanoparticles, cohabitating with pendant sulfonic groups, allowed the preparation of active bi-functional MOF-type hybrid materials (Al-ITQ-SO3H/Pd) capable of carrying out one-pot two-step oxidation-acetalization reactions, exhibiting high yield and high activity during consecutive catalytic cycles.
- Díaz, Urbano,Moreno, José María,Velty, Alexandra
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p. 3572 - 3585
(2020/06/25)
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- Method for improving activity of propylene epoxide catalyst and co-producing ketal (acetal)
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The invention provides a method for synthesizing propylene epoxide and co-producing ketal (acetal) by taking a by-product PG as a raw material in propylene epoxidation in the presence of heteropoly acid as a catalyst. Negative effects of alcohol substances to the activity of the catalyst in epoxidation reaction are eliminated, the activity of the catalyst is improved, the catalyst is used stably,meanwhile, downstream application of the by-product PG is expanded, and a preparation method for ketal (acetal) is provided. The method has the advantages of gentle reaction conditions, good catalyzing stability, good catalyst using effect, and resource utilization of the by-product.
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Paragraph 0020; 0037; 0038; 0039
(2019/01/17)
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- Facile synthesis of acetal over a supported novel Br?nsted and lewis acid ionic liquid catalyst
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A novel Br?nsted and Lewis acid ionic liquid (IL) chlorinated butyrolactam chlorozincinate (CPCl-ZnCl2) was synthesized by a hydrothermal process and characterized by Fourier transform infrared (FT-IR). The Fe-SBA-15 mesoporous materials with different Si/Fe mole ratios were prepared by direct synthesis method. The supported ionic liquid (IL/Fe-SBA-15) with various IL contents were prepared by a wet impregnation method and characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and N2 physical adsorption. The acidity was measured by FT-IR spectroscopy using pyridine as probes. The catalytic property was tested in acetalization of cyclohexanone with ethylene glycol. The results demonstrated that the IL/Fe-SBA-15 catalysts were of higher catalytic activity compared to Fe-SBA-15. Under optimal conditions, the acetalization could reach to 92.6% cyclohexanone conversion with 99.3% acetal selectivity. After 5 cycles, the cyclohexanone conversion decreased slightly. Also, the catalyst showed good catalytic property in the other acetalization of cyclohexanone and benzyl alcohol.
- Liu, Ruifeng,Dai, Liming,Zhao, Qian,Xie, Yingjie,Jiang, Tingshun
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p. 4396 - 4405
(2019/05/08)
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- Robust acidic pseudo-ionic liquid catalyst with self-separation ability for esterification and acetalization
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The novel acidic pseudo-ionic liquid catalyst with self-separation ability has been synthesized through the quaternization of triphenylphosphine and the acidification with silicotungstic acid. The pseudo-IL showed high activities for the esterification with average conversions over 90%. The pseudo-IL showed even higher activities for acetalization than traditional sulfuric acid. The homogeneous catalytic process benefited the mass transfer efficiency. The pseudo-IL separated from the reaction mixture automatically after reactions, which was superior to other IL catalysts. The high catalytic activities, easy reusability and high stability were the key properties of the novel catalyst, which hold great potential for green chemical processes.
- Shi, Yingxia,Liang, Xuezheng
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p. 1413 - 1421
(2019/05/04)
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- 8-Hydroxy-2-methylquinoline-modified H4SiW12O40: A reusable heterogeneous catalyst for acetal/ketal formation
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A heteropoly acid based organic hybrid heterogeneous catalyst, HMQ-STW, was prepared by combining 8-hydroxy-2-methylquinoline (HMQ) with Keggin-structured H4SiW12O40 (STW). The catalyst was characterized via elemental analysis, X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TG) and potentiometric titration analysis. The catalytic performance of the catalyst was assessed in the ketalization of ketones with glycol or 1,2-propylene glycol. Various reaction parameters, such as the glycol to cyclohexanone molar ratio, catalyst dosage, reaction temperature and time, were systematically examined. HMQ-STW exhibited a relatively high yield of corresponding ketal, with 100% selectivity under the optimized reaction conditions. Moreover, catalytic recycling tests demonstrated that the heterogeneous catalyst exhibited high potential for reusability, and it was revealed that the organic modifier HMQ plays an important role in the formation of a heterogeneous system and the improvement of structural stability. These results indicated that the HMQ-STW catalyst is a promising new type of heterogeneous acid catalyst for the ketalization of ketones.
- Liu, Li-Jun,Luan, Qing-Jie,Lu, Jing,Lv, Dong-Mei,Duan, Wen-Zeng,Wang, Xu,Gong, Shu-Wen
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p. 26180 - 26187
(2018/08/04)
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- Palladium on Carbon-Catalyzed Chemoselective Oxygen Oxidation of Aromatic Acetals
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The development of an unprecedented chemoselective transformation has contributed to forming a novel synthetic process for target molecules. Chemoselective oxidation of aromatic acetals has been accomplished using a reusable palladium on carbon catalyst under atmospheric oxygen conditions to form ester derivatives with tolerance of aliphatic acetals and ketals.
- Yasukawa, Naoki,Asai, Shota,Kato, Maho,Monguchi, Yasunari,Sajiki, Hironao,Sawama, Yoshinari
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supporting information
p. 5604 - 5607
(2016/11/17)
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- Phosphorus promoted SO42-/TiO2 solid acid catalyst for acetalization reaction
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A novel phosphorus modifed SO42-/TiO2 catalyst was synthesized by a facile coprecipitation method, followed by calcination. The catalytic performance of this novel solid acid was evaluated by acetalization. The results showed that the phosphorus was very effcient to enhance the catalytic activity of SO42-/TiO2. The solid acid owned high activity for the acetalization with the yields over 90%. Moreover, the solid acid could be reused for six times without loss of initial catalytic activities.
- Zhong, Shaofeng,Ou, Qiongrong,Shao, Linjun
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p. 3005 - 3008
(2015/11/27)
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- New Br?nsted-Lewis acidic quaternary ammonium ionic liquids: Synthesis, acidity determination and acidity-catalytic activity relationship
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A series of new Br?nsted-Lewis acidic ionic liquids, which are operational simplicity, high stability, low cost and applicable for scaling up, have been synthesized and their activity for acetalization was examined. The comprehensive studies on the acidity-catalytic performance relationship of the Br?nsted-Lewis acidic ionic liquids were performed. IR spectroscopy results confirmed that the new Br?nsted-Lewis acidic ionic liquids possess both Br?nsted and Lewis acid sites. The acidities were determined by Hammett method, and further studies on acidity-activity relationship revealed that the acidity played a key role in the acid-catalyzed probe reactions.
- Yi, Fengping,Gao, Jie,Zhang, Lirong,Jiang, Xiaoyan
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p. 1260 - 1264
(2015/02/19)
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- Synthesis of sulfonic acid-functionalized MIL-101 for acetalization of aldehydes with diols
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A metal-organic framework (MOF) MIL-101 bearing sulfonic acid groups (SO3H-MIL-101), was prepared through one-pot hydrothermal synthesis strategy. This MOF was systemically characterized via XRD, N2 adsorption, acid-base titration, XPS, FT-IR techniques, and elemental analysis, and then used as a heterogeneous catalyst for liquid-phase acetalizations of various aldehydes with diols. The obtained SO3H-MIL-101 shows high catalytic activity in the acetalizations due to the high utilization efficiency of its functionalized acid sites. Additionally, this catalyst can be easily recovered and reused five times in succession without significant loss of catalytic activity.
- Jin, Yan,Shi, Jing,Zhang, Fumin,Zhong, Yijun,Zhu, Weidong
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p. 167 - 171
(2014/01/17)
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- Microwave-assisted synthesis and bioactivity of some 2- dichloromethyl-1,3-dioxacycloalkanes
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A series of 2-dichloromelhyl-1,3-dioxacycloalkanes (3) was synthesized by microwave-assisted cyclization and insertion reaction. All the compounds were characterized by IR, 1H NMR, 13C NMR, MS and elemental analysis. The single crystal of compound (3b) was determined by X-ray crystallographic analysis. The preliminary bioassay results demonstrated that these compounds could alleviate acetochlor injury to maize.
- Ye, Fei,Sun, Chang-Ying,Zhao, Li-Xia,Li, Ying,Fu, Ying
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p. 159 - 164
(2019/01/21)
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- Synthesis of novel solid acidic ionic liquid polymer and its catalytic activities
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The novel solid acidic ionic liquid polymer has been synthesized through the copolymerization of acidic ionic liquid oligomers and resorcinol- formaldehyde (RF resin). The catalytic activities were investigated through the acetalization. The results showed that the PIL was very efficient for the reactions with the average yield over 99.0%. The procedure was quite simple with just one-step to complete both the reactions. The high hydrophobic BET surface, high catalytic activities and high stability gave the PIL great potential for green chemical processes. Pleiades Publishing, Ltd., 2013.
- Liang, Xuezheng
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p. 724 - 729
(2014/01/23)
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- Synthesis of a novel multi-SO3H functionalized ionic liquid and its catalytic activities
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A novel multi-SO3H functionalized ionic liquid is synthesized and a detailed account of its cata- lytic activities in acetalization and acetylation is given. The results showed that the ionic liquid is very efficient in the conventional acid-catalyzed reactions with good to excellent yields within a short reaction time. Oper- ational simplicity, small amounts required, low cost of the catalyst, high yields, scalability and reusability are the key features of this methodology, which indicates the high potentialities of the novel ionic liquid to be used in environmentally friendly processes. Pleiades Publishing, Ltd., 2012.
- Xudong, Sun,Huiquan, Xiao,Yijun, Du,Jingjing, Zhang,Xuezheng, Liang,Chenze, Qi
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p. 301 - 305
(2012/10/29)
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- Acetalization of carbonyl compounds catalyzed by acidic ionic liquid immobilized on silica gel
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Imidazolium-silica heterogeneous catalyst (SG-[(CH2) 3SO3H-HIM]HSO4) was prepared by immobilization of acidic ionic liquid 1-(propyl-3-sulfonate) imidazolium hydrosulfate ([(CH2)3SO3H-HIM]HSO4) on silica-gel using tetraethoxysilane (TEOS) as silica source in this study. The properties of the samples were characterized by FT-IR, SEM and TG/DSC. The results suggested that [(CH2)3SO3H-HIM]HSO4 had been successfully immobilized on the surface of silica-gel and the immobilized ionic liquid catalyst SG-[(CH2)3SO 3H-HIM]HSO4 had good thermal stability. The original smooth surface of silica-gel was covered with [(CH2) 3SO3H-HIM]HSO4 and a rough surface of SG-[(CH2)3SO3H-HIM]HSO4 was formed, but the size of particles had no obvious change. Moreover, SG-[(CH 2)3SO3H-HIM]HSO4 exhibited high catalytic activity for a series of acetalization and could be recovered easily. After reused for 10 times in the synthesis of benzaldehyde ethanediol acetal, the catalyst could still give satisfactory catalytic activity.
- Miao, Jinmei,Wan, Hui,Shao, Yanbing,Guan, Guofeng,Xu, Bin
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experimental part
p. 77 - 82
(2011/11/07)
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- Synthesis of a novel ionic liquid with both Lewis and Br?nsted acid sites and its catalytic activities
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The novel ionic liquid with both Lewis and Br?nsted acid sites has been synthesized and its catalytic activities for acetalization and Michael addition were investigated carefully. The novel ionic liquid was stable to water and could be used in aqueous solution. Furthermore, the molar ratio of the Lewis and Br?nsted acid sites could be adjusted according to different reactions. The results showed that the novel ionic liquid was very efficient for the traditional acid-catalyzed reactions with good to excellent yields in short time.
- Liang, Xuezheng,Qi, Chenze
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experimental part
p. 808 - 812
(2012/01/04)
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- Non-acid catalytic acetalisation of aldehydes with diols in ionic liquids
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The acetalisation of aldehydes with diols to corresponding 1,3-dioxolanes has been accomplished using ionic liquids as catalyst and reaction media. In the reaction process the removal of water produced and other catalysts were not necessary. High conversion and good selectivity were obtained when using HMImBF4, which could be easily recycled and reused.
- Zhang, Fan,Xu, Dan-Qian,Luo, Shu-Ping,Liu, Bao-You,Du, Xiao-Hua,Xu, Zhen-Yuan
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p. 773 - 774
(2007/10/03)
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- 2,4,4,6-Tetrabromo-2,5-cyclohexadienone (TABCO) as a versatile, efficient, and chemoselective catalyst for the acetalization and transacetalization of carbonyl compounds, the preparation of acetonides from epoxides and acylals (1,1-diacetates) from aldehydes
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The efficient and chemoselective preparation of acetals and ketals from carbonyl compounds, transacetalization reactions, the conversion of epoxides to acetonides, and the preparation of acylals from aldehydes in the presence of catalytic amounts of 2,4,4,6-tetrabromo-2,5-cyclohexadienone (TABCO) are described.
- Firouzabadi, Habib,Iranpoor, Nasser,Shaterian, Hamid Reza
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p. 2195 - 2205
(2007/10/03)
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- Chemistry of dioxacycloalkanes: VII. Synthesis and properties of substituted 1,3-dioxolanes derived from carbocyclic aldehydes
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Reactions of 3-cyclohexenecarbaldehyde, 6-methyl-3-cyclohexenecarbaldehyde, bicyclo[2.2.1]-hept-5-ene-endo-2-carbaldehyde, and benzaldehyde with 1,2-propanediol and 3-chloro-1,2-propanediol gave the corresponding 2,4-substituted 1,3-dioxolanes. Their reactions with peroxyacetic acid, bromine, dichlorocarbene, and nucleophiles were studied. The effect of the substituents in the diol and aldehyde on their relative reactivity is discussed.
- Kerimov
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p. 136 - 140
(2007/10/03)
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- Preparation of salicylic acid resin supported FeCl3 lewis acid catalyst and its application in organic synthesis
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The catalytic effects of salicylic acid resin supported FeCl3 catalyst on the esterification of alcohol and carboxylic acid and on the acetalization (ketal formation) of aldehyde (ketone) and alcohol have been investigated.This catalyst is convenient to use, noncorrosive, easy to be separated from reactants and can be repeatedly used.
- Huirong, Yang,Yingde, Li Bina Cui
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p. 1233 - 1238
(2007/10/03)
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- Preparation of optically active α-Silylcarbonyl compounds using asymmetric alkylation of α-Silylacetic esters and asymmetric metal-carbene insertion into the Si-H bond.
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Substituted α-silylacetic esters have been prepared in good yields and with reasonable diastereoselectivities by three different routes. The first two involved alkylation of the parent α-silylacetic ester enolates, with the chiral auxiliaries being present either on silicon or on the ester function. The third route involving asymmetric insertion of metal-carbenoids into the Si-H band was found to afford better diastereoselectivities, using pantolactane as chiral auxiliary.
- Landais, Yannick,Planchenault, Denis
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p. 2855 - 2870
(2007/10/03)
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- Acetals by AlFe-pillared montmorillonite catalysis
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AlFe-pillared montmorillonite is an efficient catalyst for acetals preparation in CH2Cl2 at room temperature.
- Cramarossa, Maria Rita,Forti, Luca,Ghelfi, Franco
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p. 15889 - 15894
(2007/10/03)
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- Reactions of Benzylamine and Selected Ring- and N-Substituted Derivatives with Iodine, Including a Synthesis for Benzonitriles
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Benzylamine and its ring-substituted derivatives are smoothly dehydrogenated to iminium ions by iodine in a non-nucleophilic polar solvent such as acetonitrile.If excess amine is used, condensation of the iminium ion with free benzylamine occurs, affording N-benzylidenebenzylamines.However, when t-butylamine is present as a co-solvent, further dehydrogenation takes place and good to excellent yields of benzonitriles are obtained.N-Monosubstituted benzylamines are converted to N-benzylidene amines which, in the presence of t-butylamine, undergo transamination forming N-benzylidene-t-butylamine.In acetonitrile, the iminium species resulting from N-methylbenzylamine condenses with two molecules of free amine to give N,N'-dibenzyl-N,N'-dimethyl-1-phenylmethanediamine.Treatment of N-methylbenzylamine with iodine in the presence of alcohols as co-solvents leads to the formation of acetals in low yields.N,N-Disubstituted benzylamines form tertiary iminium ions which undergo hydrolysis on aqueous workup., liberating benzaldehyde and the appropriate secondary amine fragment.In the presence of t-butylamine, N-benzylidene-t-butylamine is once again obtained.Probable mechanisms for these reactions are outlined.
- Goosen, Andre,McCleland, Cedric W.,Sipamia, Allworth M.
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p. 311 - 332
(2007/10/02)
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- Transacetalation: a convenient, nonaqueous method for effecting the deprotection of isopropylidene and benzylidene derivatives of sugars
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Sugar isopropylidene and benzylidene derivatives can be readily deprotected under nonaqueous conditions by treatment of a dichloromethane solution of the protected sugar with an excess of a sacrificial glycol in the presence of a catalytic amount of p-toluenesulfonic acid.The reaction is conveniently monitored by GLC, and the fully or partially deprotected product precipitates from solution.
- Andrews, Mark A.,Gould, George L.
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p. 141 - 148
(2007/10/02)
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- N-Benzyl Pyridinium Salta as New Useful Catalysts for Transformation of Epoxides to Cyclic Acetals, Orthoesters, and Orthocarbonates
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In the presence of catalytic amount of N-(4-methoxybenzyl)-2-cyanopyridinium hexafluoroantimonate, the reaction of a few epoxides with aldehydes, ketones, lactones, and carbonates efficiently afforded corresponding cyclic acetals, orthoesters, and orthocarbonates under mild conditions.
- Lee, Sang-Bong,Takata, Toshikazu,Endo, Takeshi
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p. 2019 - 2022
(2007/10/02)
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- Synthese d'acetals cycliques dans des conditions douces; Applications a l'acetalisation du chloramphenicol
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Acetalization of 1-2 and 1-3 diols, even as sterically crowded as chloramphenicol, by carbonyl derivatives with substituents of various sizes has been performed at room temperature under mild conditions, by using heterogeneous catalysis (sulfonated polystyrene) in the presence of molecular sieves.Several new acetals of chloramphenicol have thus been obtained in good yields, isolated and characterized.
- Meslard, J. C.,Subira, F.,Vairon, J. P.,Guy, A.,Garreau, R.
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- DETERMINATION OF ENANTIOMERIC PURITY OF GLYCOLS RCHOHCH2OH
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The enantiomeric purity of primary-secondary glycols, RCHOHCH2OH, is conveniently determined by conversion to a pair of epimeric 1,3-dioxolanes through condensation with benzaldehyde, followed by nmr spectroscopy in presence of a chiral shift reagent with observation of the benzylic protons.
- Eliel, Ernest L,Ko, Kwang-Youn
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p. 3547 - 3550
(2007/10/02)
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- A FACILE CLEAVAGE OF BENZYLIDENE ACETALS WITH DIISOBUTYLALUMINUM HYDRIDE
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Benzylidene acetals of 1,2- and 1,3-glycols are easily cleft by diisobutylaluminum hydride in a toluene solution at 0 deg C - room temperature to give the corresponding monobenzyl ethers of the glycols.In general the reaction proceeds excellently in regioselective manner depending on the stereochemical environment.
- Takano, Seiichi,Akiyama, Masashi,Sato, Seiji,Ogasawara, Kunio
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p. 1593 - 1596
(2007/10/02)
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- Investigation of the Effectiveness of Various 1-Dialkylamino-1-methoxycarbenium-Methyl Sulfates in the Course of Acetalization
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The rate of dimethyl ketal formation from acetone and methanol in the presence of several 1-dialkylamino-1-methoxycarbenium methyl sulfates 1a, 5a-g is studied.The fastest rate was observed in the case of 5c.In the presence of 5c, the reaction of carbonyl compounds with either methanol or 1,2-diols gave the dimethyl ketals 6 and 1,3-dioxolanes 7, respectively.
- Kantlehner, Willi,Gutbrod, Heinz-Dieter,Funke, Bernd
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p. 246 - 252
(2007/10/02)
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